The long-term objective of this project is to characterize and understand the mechanism of action and regulation of dopamine-beta-hydroxylase (DBH). The immediate goals have been to measure the redox potential of DBH and to study the effects of substrates and products on the active site of the enzyme. The effect of Fe(CN)6 4- as an electron donor for DBH has also been studied. BIBLIOGRAPHIC REFERENCES: Walker, G.A., Kon, Hidea and Lovenberg, W.: An investigation of the copper site(s) of dopamine-beta-hydroxylase by electron paramagnetic resonance. Biochimica et Biophysica Acta 482: 309-322, 1977. Kafka, M.S., Blumenthal, R., Walker, G. and Pollard, H.: The effect of dopamine-beta-hydroxylase on the electrical conductance of biomolecular lipid membranes. Membrane Biochem. In press (1977).